Sir Alex Ferguson has told Manchester United winger Luis Nani that he must perform to a consistently high level if he is to hold down a place in the Premier League leaders’ team, BBC Sport has reported.Ferguson lavished praise upon the Portugal international, declaring him to be one of the most talented players in Europe, and stressing he wants Nani to remain at Old Trafford. The club and the player are locked in contract negotiations, with Nani having around 18 months left on his current deal, but a lack of first team football is thought